i have min-max BLMs set to 128 and CL coolant set quite high. i am seeing OL operation. Q is must i disconnect the battery cable for 10 sec to reset BLMs? i would expect i need to as the ECU is using stored BLMs to achieve 14.7/1 on last CL run. i did so and i believe i am not running off my VE table OL at 122 BLM as that was my wiish. 122 BLM OL is 14.00/1 idle and 16.0-17.0/1 for cruise. did this to help with AE function as i believe i was too lean on all my prior tunes.

comments?

 

Ya lost me.
If you want O/L, just set the CTS enable high.

Without BLs, and C/L you can get to where the INT is just chasing itself around every time you hit the gas.

 

as is stated i set blm high and low threshold to 128 so no NEW correction occuring and i am not seeing anly data in win ALDL for BLM. i did not set INT to 128 and 128. should i have? coolant constant for CL as stated.

i was of opinion that the ECU stores the "corrections" and will modify my VE table to what it last saw. for instance if i had a 131 BLM for cell 30 map and 2000 rpm would it not provide one and only one correction to my OL VE tables in the .bin i just ran. i am thinking if i disconnected the battery it would reset the ECU and not provide that correction as 128/128 for BLM threshold.

i believe i was tought disconncecting battery provides a fresh 128 clearing BLM corrections held in ECU, not in .bin.

 

If you forced the BLM's to 128, then you are getting a BLM of 128, not whatever value is stored in the memory cells of the ECM that are maintained at poweroff.

locking the blm to 128 is not just preventing "new" correction, it's preventing ANY correction. that's the beauty of it. locked BLm at 128 means "use my VE specified values with no corrections".

it doesn't matter what the ECM has learned before. even if you learned in all 108's, as soon as you pop in a chip with locked BLM of 128/128, that's where you're going to be at. 128/128. not what was learned before.

i haven't verified this on the ecm bench today but i remember it working like this last time i locked the blm's.

 

so in that case no need to lock INT to 128/128 as it will not update BLM's? reason i ask is that i did not touch INT in constants. only BLM's.

now i am forced to add MAP input to WB02 log so i can reference what cell i am in for any one specific rpm/map area.

 

if you don't lock the INT, it will still fluctuate and have some (relatively) minor effect on the fueling. It just won't update the BLM.

If you aren't familiar with how the INT/BLM inter-operate, read up on it.

If your goal is to run purely and completely off the VE table with no compensation at all, then you need to lock both the BLM and the INT.

locked to 128/128 means BLM/INT locked to 128 each.

 

thanks. next burn i lock INT too.

i like OL !

 

If the CL coolant temperature is set high enough (as you mentioned in your first post) then the INT doesn't need to be locked.

I haven't quite figured out if you want to run OL or just want the INT's to run. To run Open Loop only, lock the BLMs at 128, set the closed loop coolant enable to 151°C, and disable the O2 DTCs (13, 44 & 45, IIRC).

The only reason to lock the BLMs at 128 is so old learned values are not used. On some ECMs this doesn't matter as key on ALWAYS resets them to 128 ('ala the '8746). Can also do the battery dance for the same affect.

RBob.

 

RRob: my intent is to run OL. my WB logs clearly show OL functional as does the flag in winALDL. now i was hopeing to get OL yet still see what the BLM are reporting yet having no effect so as to determine if cells are proportional. I have burned OL then with same fuel values burned a CL to determine if i have a consistent 122 across the board. my OL idle is steady 13.5/1 A/F, cruise is 15.5 to 16/1 and steady. when i run CL my idle(900 rpms) is erratic as far as A/F with surging as is cruise. cruise i see anywhere from 14.7 to 25/1 with erratic reporting. some of that may be my Bosch NB 02 sensor quality lacking.

please explain: "quote" O2 DTCs (13, 44 & 45, IIRC). what do i do here? i have tunercat.

 

Diagnostic Trouble Codes (DTC), also called the malfunction flags. The 13, 44, and 45 are for O2 sensor diagnostics. In open loop it is common to trip these with the SES then illuminating. Just uncheck them in the bin editor.

RBob.

 

did not trip. but will uncheck. thanks for the tip